Pressure gauge



Get. 4, 1949. C, R, A, GRANT y 2,483,635

PRESSURE GAUGE Filed oct. s, 1946 5 u C124 /f /3 Charles E Arant',

ATTORNEY INVENTOR.

Patented Oct. 4, i949 PRESSURE GAUGE Charles Robert Archibald Grant,London, England Application October 3, 1946, Serial No. 700,950 In GreatBritain July 16, 1945 2 Claims. 1

This invention relates to pressure gauges and has for its object toprovide a direct acting gauge, that is to say a gauge wherein a Bourdontube has its free end connected substantially directly to a pointermoving over a dial.

According to the present invention a Bourdon tube has its free endconnected by a link to a crank pin on a spindle carrying a pointermoving over a dial. In order to take up backlash the link is preferablyin the form of a strip of resilient material such as spring steel. Oneend of the link may be connected adjustably to the free end of theBourdon, or may include in its length an adjustable U-shaped loop.

The link may be provided at one end with an end piece for attachment tothe free end of the Bourdon tube, whilst its other end is suitablyshaped for engagement with the crank pin.

The invention will now be described by way of example Iwith reference tothe accompanying drawings, wherein:

Figure 1 is a rear view in elevation and partially in section on lineI-I of Fig. 2 of a pressure gauge embodying the present invention;

Figure 2 is a section on the line 2-2 of Figure l but w1th the pointerin the broken line position of Fig. 1 and with the opposite end of theBourdon tube and connecting link shown in phantom lines; and

Figures 3 and 4 show details.

Referring first to Figures 1 to 3, a pressure gauge is provided in theusual manner with a hollow post I, of which one end is screw threadedexternally as shown at 2 for engagement with a container, pipe or thelike in which is contained, or through which passes, a fluid underpressure. The end of the post is preferably forked as indicated at 3, 4and in the forked end 3, li is rotatably mounted a spindle 5, to whichis secured a pointer 5 for movement over a graduated dial (not shown)secured to the post I. To the post I is also secured one end of aBorudon tube l, which communicates with the hollow interior of the postI. The other or free end l of the Bourdon tube 'I is connected by a link8 to a crank pin 9 on the pointer spindle 5. For this purpose thepointer spindle 5 is cranked, the cheeks I9, II of the cranked portionbeing in the form of circular discs, mounted in circular openings in theparts 3, d, between which the end of the link 8 engages with the crankpin 9. The other end of the link 8 is connected to the free end 1 of theBourdon tube l by an adjustable connection so as to enable the pointer 6to be adjusted conveniently with the Zero position of the scale. Theadjustable connection, as shown in Figs. 1-3, may comprise a slot I3 inthe end of the strip B and a screw l2 inserted through the slot andthreaded into an aperture in the free tube end l.

The link or strip 8, at the end thereof adapted to engage with the crank9, is preferably formed as a resilient loop I4, which enables it to beengaged readily and effectively with the crank pin 9, whilst its otherend is slotted, as shown at I3, for adjustable connection to the freeend of the Bourdon tube I by the screw l2.

Instead of connecting the strip 8 adjustably to the free end I of theBourdon tube 1, the strip 8, as shown in Figure 4, is providedintermediate its ends with an adjustable U-shaped loop I5, which enablesthe pointer 6 to be adjusted relatively to the zero position of thedial. In this case the strip 8 is provided with an end piece I6 forsecuring to the free end 'l' of the Bourdon tube 1.

A gauge according to the invention is inexpensive to produce, simple inconstruction, and strong. Backlash is taken up by making the link 8resilient. By forming the link 3 of strip material a large area ispresented for Wear, with the maximum lightness.

What I claim is:

1. In a pressure gauge the combination comprising a hollow post having aforked end, a Bourdon tube secured at one end to said post incommunication with the interior thereof, a spindle rotatably mounted insaid forked end, a pointer secured to said spindle, said forked endhaving circular openings therein, circular discs on said spindle, saiddiscs engaging said circular openings, a crank pin located between saiddiscs, a link having a resilient loop at one end thereof, said resilientloop engaging with said crank pin, said link having a slot in its otherend, and a screw engaging said slot and secured to the other end of saidBourdon tube.

2. In a pressure gauge the combination'comprising a hollow post having aforked end, a Bourdon tube secured at one end to said post incommunication with the interior thereof, a spindle rotatably mounted insaid forked end, a pointer secured to said spindle, said forked endhaving circular openings therein, circular discs on said spindle, saiddiscs engaging said circular openings, a crank pin located between saiddiscs, a link having a resilient loop at one end thereof, said resilientloop engaging with said crank pin, said link being connected at itsother end directly l to o he other ond of said Bourdon tobe, oaid linkUNITED STATES PATENTS having an adJustable loop mtermedxate 1ts ends.

CHARLES ROBERT ARCHIBALD GRANT. Number Name Date 1,937,879 Esbaugh Dec.5, 1933 REFERENCES CITED 5 1,987,673 Ferrier Jan, 15, 1935 2,247,102Sugden et al June 24, 1941 The following references are of record in thefile of this patent:

